plural aculei
: a sharp-pointed process
specifically : an insect's ovipositor especially when modified into a sting

Word History


borrowed from New Latin, going back to Latin, "stinger, spine (of a fish), sharp point, barb," from acū-, stem of acus "needle" + -leus, noun suffix (perhaps originally diminutive)

First Known Use

1702, in the meaning defined above

Time Traveler
The first known use of aculeus was in 1702

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Dictionary Entries Near aculeus

Cite this Entry

“Aculeus.” Dictionary, Merriam-Webster, Accessed 13 Jun. 2024.

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